3d printing

Abstract

Disclosed are a three-dimensional (3D) printed object and a method of printing the same. The method comprises determining whether an edge of the current base layer protrudes beyond an edge of a previous base layer. Based on determining that the edge of the current base layer does not protrude beyond the edge of the previous base layer, the method comprises printing a plurality of the current outer wall color layers in an edge region of a surface of an object and printing the current base layer in a middle region of the surface of the object to obtain an additively printed object. A thickness of the stacked current outer wall color layers equals a thickness of the current base layer

What is claimed is: 
     
         1 . A method of printing an object, comprising:
 determining, by a computing device, a printing trajectory of a current base layer;   determining, based on the printing trajectory of the current base layer, whether an edge of the current base layer protrudes beyond an edge of a previous base layer; and   based on determining that the edge of the current base layer does not protrude beyond the edge of the previous base layer:
 printing a plurality of current outer wall color layers in an edge region of a surface of the object; and 
 printing the current base layer in a middle region of the surface of the object to obtain an additively printed object, wherein a thickness of the plurality of current outer wall color layers equals a thickness of the current base layer, and the edge region adheres to the middle region. 
   
     
     
         2 . The method according to  claim 1 , wherein the printing the plurality of current outer wall color layers and printing the current base layer comprises:
 printing a first subset of the plurality of current outer wall color layers in the edge region of the surface of the object until a thickness of the first subset of the plurality of current outer wall color layers reaches half of the thickness of the current base layer; and   printing a second subset of the plurality of current outer wall color layers on a side of the printed first subset of the plurality of current outer wall color layers until a thickness of the plurality of current outer wall color layers reaches the thickness of the current base layer.   
     
     
         3 . The method according to  claim 1 , wherein the printing the plurality of current outer wall color layers and printing the current base layer comprises:
 printing the current base layer by adhering the current base layer to the plurality of the current outer wall color layers in the middle region of the surface of the object to obtain an additively printed object, wherein sides of the plurality of current outer wall color layers close to the current base layer are flush.   
     
     
         4 . The method according to  claim 1 , wherein the printing the plurality of the current outer wall color layers and printing the current base layer comprises:
 printing a current fixed color layer in an edge region of one of the plurality of current outer wall color layers, wherein a side of the current fixed color layer close to the middle region protrudes beyond a side of the one of the plurality of current outer wall color layers close to the middle region.   
     
     
         5 . The method according to  claim 4 , further comprising:
 based on determining that the edge of the current base layer protrudes beyond the edge of the previous base layer, printing a current outer wall transmissive layer and the current fixed color layer alternately and stackedly in the edge region of the surface of the object.   
     
     
         6 . The method according to  claim 1 , further comprising:
 obtaining a printing trajectory of a bottom surface layer;   printing the bottom surface layer based on the printing trajectory of the bottom surface layer; and   printing a first end surface color layer on a side of the bottom surface layer.   
     
     
         7 . The method according to  claim 6 , further comprising:
 printing a second end surface color layer on a side of the object away from the bottom surface layer.   
     
     
         8 . The method according to  claim 1 , wherein the determining the printing trajectory of the current base layer comprises:
 obtaining an overall shape of a 3D printed object;   slicing the overall shape based on thicknesses of base layers to obtain printing trajectories of a plurality of layer structures of the 3D printed object;   retracting the printing trajectory of each of the layer structures by a preset distance; and   obtaining a printing trajectory of each of the base layers corresponding to the layer structures, and the method further comprises obtaining a printing trajectory of each of color layers based on the retracted printing trajectory.   
     
     
         9 . The method according to  claim 1 , wherein the printing the plurality of current outer wall color layers and printing the current base layer comprises:
 printing the plurality of current outer wall color layers in the edge region of the surface of the object using photocuring ink, and printing the current base layer in the middle region of the surface of the object using fused deposition modeling (FDM).   
     
     
         10 . The method according to  claim 1 , further comprising:
 repeating the determining and the printing steps until a 3D object is completed.   
     
     
         11 . A three-dimensional (3D) printed object, comprising:
 a body comprising a plurality of base layers; and   a color shell wrapping around an exposed side of the body and comprising a plurality of outer wall color layers, wherein:   the plurality of outer wall color layers and the plurality of base layers are stacked on a same horizontal plane, and   a thickness of each one of the outer wall color layers is less than a thickness of one of the plurality of the base layers.   
     
     
         12 . The 3D printed object according to  claim 11 , further comprising one or more of a vertical sidewall, an inwardly sloping sidewall, and an overhanging sidewall, wherein:
 sides of the plurality of base layers corresponding to the vertical sidewall are flush, and   sides of the plurality of outer wall color layers corresponding to the vertical sidewall are flush.   
     
     
         13 . The 3D printed object according to  claim 12 , wherein:
 in a direction from a bottom surface to a top surface of the 3D printed object, edges, on a side of the plurality of base layers corresponding to the inwardly sloping sidewall are shortened layer by layer, and edges, on a side, of the plurality of outer wall color layers corresponding to the inwardly sloping sidewall are inclined layer by layer to a side close to the body; and   in a direction from the bottom surface to the top surface of the 3D printed object, edges, on a side of the plurality of base layers corresponding to the overhanging sidewall are lengthened layer by layer, and edges, on a side of the plurality of outer wall color layers corresponding to the overhanging sidewall are inclined layer by layer to the side away from the body.   
     
     
         14 . The 3D printed object according to  claim 12 , further comprising a plurality of fixed color layers, wherein:
 the plurality of fixed color layers and the plurality of outer wall color layers are stacked;   a side of each of the plurality of fixed color layers close to the body protrudes beyond a side of a corresponding outer wall color layers close to the body; and   a part of each of the fixed color layers, which is close to the body and protrudes beyond a corresponding outer wall color layers, is inserted into the body to adhere to two adjacent base layers.   
     
     
         15 . The 3D printed object according to  claim 14 , wherein each of the plurality of base layers comprises a plurality of outer layers and an inner layer, and a thickness of each of the plurality of outer layers is less than a thickness of the inner layer. 
     
     
         16 . The 3D printed object according to  claim 15 , wherein:
 outer layers of the plurality of base layers corresponding to the overhanging sidewall are outer wall transmissive layers;   the outer wall transmissive layers extend toward a side away from the body until being exposed; and   each of the plurality of fixed color layers is interposed between every two adjacent outer wall transmissive layers.   
     
     
         17 . The 3D printed object according to  claim 11 , further comprising:
 an end surface color layer and an end surface transmissive layer, wherein:   the body comprises at least one end surface, and the end surface color layer adheres to the end surface,   the end surface comprises a bottom surface, a bridging bottom surface, and a top surface, and   if the end surface is the bottom surface or the bridging bottom surface, the end surface transmissive layer adheres to a side of the end surface color layer away from the body.   
     
     
         18 . A method of printing an object, comprising:
 determining, based on a printing trajectory of a current base layer, whether an edge of the current base layer protrudes beyond an edge of a previous base layer;   based on determining that the edge of the current base layer does not protrude beyond the edge of the previous base layer, printing a layer comprising:
 the current base layer on top of the previous base layer; and 
 a plurality of current outer wall color layers on sides of the current base layer, wherein a thickness of the plurality of current outer wall color layers equals a thickness of the current base layer. 
   
     
     
         19 . The method according to  claim 18 , wherein the printing the current base layer comprises printing the current base layer by adhering the current base layer to the plurality of the current outer wall color layers in a middle region of a surface of the object to obtain an additively printed object, wherein sides of the plurality of current outer wall color layers close to the current base layer are flush. 
     
     
         20 . The method according to  claim 18 , wherein the determining the printing trajectory of the current base layer comprises:
 obtaining an overall shape of a 3D printed object;   slicing the overall shape based on thicknesses of base layers to obtain printing trajectories of a plurality of layer structures of the 3D printed object;   retracting the printing trajectory of each of the layer structures by a preset distance; and   obtaining a printing trajectory of each of the base layers corresponding to the layer structures, and the method further comprises obtaining a printing trajectory of each of color layers based on the retracted printing trajectory.